Question 1:

B. negative feedback

Explanation:

• Negative feedback is the process by which a change in the body triggers a response that reverses the change, returning the body to its set point (e.g., lowering body temperature when it rises too high).

• Positive feedback amplifies the change (e.g., in childbirth).

• Digestion and excretion are not homeostatic feedback mechanisms.

*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 2:

The correct answer is A. pituitary.

Reasoning:

• The hypothalamus (part of the brain) detects changes in blood water content (osmoreceptors).

• The hypothalamus then signals the pituitary gland to release ADH (antidiuretic hormone), which acts on the kidneys to adjust water reabsorption.

• While the kidney (B) is the effector that responds to ADH, the receptor and control centre for water balance is primarily in the hypothalamus/pituitary.

• The liver (C) and pancreas (D) are not directly involved in monitoring blood water content.

So, A. pituitary is correct.

*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 3:

The correct answer is C. ADH (antidiuretic hormone).

Reasoning:

• ADH is released by the pituitary gland in response to high blood concentration (low water content).

• It increases the permeability of the kidney tubules to water, allowing more water to be reabsorbed back into the bloodstream, thus concentrating the urine.

• Insulin (A) regulates blood glucose. Testosterone (B) is a sex hormone. Adrenalin (D) is involved in the fight-or-flight response.

*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 4:

The correct answer is B. osmosis.

Reasoning:

• When blood water content is too low, the blood becomes more concentrated (higher solute concentration) than the fluid inside body cells.

• Water will move out of the cells and into the blood by osmosis (the net movement of water across a selectively permeable membrane from an area of higher water concentration to lower water concentration).

• Diffusion (A) refers to movement of solutes, not specifically water. Dehydration (C) is the overall condition of water loss, not the cellular process. Homeostasis (D) is the maintenance of a stable internal environment, not the process of water movement.

*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 5:

The correct answer is C. 37°C.

Reasoning:
The normal core body temperature for humans is approximately 37°C (98.6°F), maintained through homeostatic mechanisms.

*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 6:

The correct answer is A.

Structure A is the coiled tube leading to the surface, which characterizes a sweat gland.

*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 7:

The correct answer is C.

Reasoning:

• In hot weather, the body tries to lose heat.

• The hair erector muscles relax, allowing the hairs to lie flat on the skin.

• This reduces the layer of trapped air near the skin, allowing heat to escape more easily.

*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 8:

The correct answer is D.

Vasoconstriction is the narrowing of blood vessels to reduce blood flow to the skin surface and conserve heat. Structure D represents the blood vessels (arterioles/capillaries) in the dermis.

*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 9:

The correct answer is D.

Reasoning:

• Vasoconstriction means blood vessels near the skin surface narrow.

• This reduces blood flow to the skin, so less heat is radiated from the skin → heat radiated decreases.

• With less warm blood flowing near the surface, the skin may appear blue/pale rather than flushed red.

*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 10:

The correct answer is D. the hypothalamus.

Reasoning:

• The hypothalamus acts as the body's thermostat. It receives signals from temperature receptors in the skin and blood, and coordinates responses (e.g., sweating, shivering, vasodilation/vasoconstriction) to maintain a stable core temperature.

• The pituitary (A) releases hormones but is not the main control centre for temperature. Nerve endings in the skin (B) are receptors, not the control centre. The liver (C) generates heat through metabolism but does not control temperature regulation.

*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.